All depends on what's wrong with it. There could be worn teeth on the ring gear, a defective over-running clutch / drive gear, or more commonly, rust buildup on the starter drive's shaft. That rust, or gunked up hardened grease can stop the drive gear from fully engaging the ring gear.
If there's worn teeth on the ring gear, turning the engine a little by hand will get it to crank.
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Monday, August 1st, 2011 AT 3:44 AM